Device for chopping the stalks after the ears of corn have been cut off in a combine harvester

ABSTRACT

The object of the invention is a straw-cutting machine which is positioned behind the grain separation devices of a combine harvester and whose separation organs chop the stalks falling from the straw walkers into short pieces. The aim of the invention is by means of a special design of the separation organs to reduce the required driving power, to chop and disintegrate stalks falling onto the straw-cutting machine in a lateral position or a longitudinal direction uniformly into the smallest possible pieces and subsequently to disperse the chopped stalks as uniformly as possible over the whole cutting width on the soil. This is achieved by positioning in uniform distribution fixed tang plates serrated on their front sides on the mantle of a chopping cylinder which tang plates separate laterally positioned stalks in a drawing cut in a uniform, relatively thin veil over cutting knives fixed rigidly, but equipped with springs on the chopping floor. The stalks taken up in a longitudinal direction by the tang plates are separated separately in a following device. In this process, this device can comprise a simple counter bar positioned directly after the chopping knives. For stalks which are more difficult to separate, optionally a cylinder-type chopper or several flywheel choppers can also be located after the lateral cutting device.

BACKGROUND OF THE INVENTION

The object of the invention is a straw-cutting machine which ispositioned behind the grain separation devices of a combine harvesterand whose separating organs chop the stalks falling from the strawwalkers into short pieces which are discharged through a distributionbox and deposited on the floor spread over the cutting width.

Straw-cutting machines of a conventional design generally have cutterknives supported in a freely movable manner on a cylinder tube whichcutter knives take up the falling stalks and beat against fixed positionopposite cutting knives. In this process, the stalks are cut up whileconsuming high power.

Furthermore, this type of construction has the disadvantage that stalkspassing roughly in a longitudinal direction over the straw walkers areonly separated insufficiently. This is bad in that due to new culturesthe straw is becoming ever shorter and ever more stable and thus passesover the straw walkers in a longitudinal direction in a larger quantity.

But longer straw in a large quantity is only insufficiently distributedbehind the distributor hood, it can only be poorly worked into the soiland it rots badly.

SUMMARY OF THE INVENTION

The object of the invention is to reduce the power requirements of thestraw-cutting machine over known versions, to cut and disintegrate thestraw shook out in uniform short pieces irrespective of whether it fallsfrom the straw walker in a lateral position or longitudinal directionand to distribute it uniformly on the soil over the whole cutting widthwith a powerful air flow.

In the process, the foreign bodies carried with the stalks should passthrough the straw-cutting machine without damaging or destroying it.

This is achieved in accordance with the invention by having instead ofthe conventional chopping knives supported in a freely movable manner ona cylinder tube, tangs fixed rigidly on a cylinder roll and provided ontheir front sides with an aggressive, eccentrically relieved serrationwhich tangs take up the stalks to be separated and pull them in arelatively thin stalk veil in a drawing cut over chopping knives with asharp cutting edge fixed on the chopping floor whereby the stalks areseparated with a relatively low energy consumption.

The width of the tangs corresponds here approximately to the width towhich the laterally positioned stalks should be cut.

The tangs are positioned uniformly distributed in any number of rows ina spiral shape on the circumference of a cylinder roll with the firsttang of a row in each case lying in a longitudinal direction of thecylinder roll at the same height as the last tang of a row on theopposite side.

By means of this design, the stalks pass through the straw-cuttingmachine in a relatively thin veil with practically only two tangs ineach case frictionally contacting the stalks to be separated beingseparated by the chopping knives.

In this way, a constant, relatively low torque results andcorrespondingly a low constant power requirement.

In this process, tang on tang can lie in a row with a gap between eachthrough which the fixed position chopping knife can pass. But one tangeach can also be omitted from a row so that the number of cuts and thusthe power requirement is reduced.

One special advantage of the wide tangs is also that they first generatea powerful wind around the cylinder mantle and then securely dischargethe chopped stalks through the spade-shaped design.

The fixed position chopping knives are fixed in pairs on rotatingknife-bearers supported on a knife floor positioned outside and roughlyparallel to the cutting floor. Here, the knife-bearers are provided withstops which are pressed against the knife floor by means of springs. Thechopping knives themselves protrude into the chopping box through slitsin the knife floor and the cutting floor. If a hard foreign body istaken up by the tangs, the chopping knives yield to the outside so thatthe foreign body can pass the cutting device without damaging it. Theknife floor can be retracted so far as one unit with the knife-bearersand the chopping knives that the chopping knives are outside the cuttingarea. If the distribution box is swivelled out at the same time, it ispossible to deposit the stalks over the chopping cylinder in an uncutmanner in a swathe. In this process, the stalks are bent anddisintegrated and are so better suited for further utilization. Thanksto the previously described lateral cutting device, stalks primarilypassing laterally through the straw-cutting machine are separated.

A further feature of the invention is that optionally different cuttingdevices are positioned after the lateral cutting device by means ofwhich stalks passing through the straw-cutting machine in a longitudinaldirection are separated into short pieces. In the simplest version,pivotable opposite cutting plates are positioned under the choppingknives on the cutting floor which opposite cutting plates haveeccentrically relieved serrations on their front sides, the serrationsof the opposite cutting plates agreeing in profile to the serrations ofthe tang plates and protruding into these up to a distance parallel onall sides of less than 3 mm.

In this way, straw passing through the straw-cutting machine lengthwaysis separated and thus cut into pieces along its length at that point atwhich a tang plate passes an opposite cutting plate.

These counter-bars are distributed in width in segments over thechopping cylinder with each segment being held in engagement with thetangs by a single spring. If a hard foreign body passes through thestraw-cutting machine, these segments yield backwards in accordance withtheir width.

So that the chopped stalks discharged from the distribution box aredistributed securely over the whole cutting width, radial blowers arelocated at both ends of the cylinder roll and fixed securely to it,which radial blowers suck in air from the side of the straw-cuttingmachine housing and blow it into the distribution box. For stalks whichare more difficult to chop and if a high quantity of longitudinallypositioned stalks is to be cut, as is shown in FIG. 9 and FIG. 10,instead of the opposite cutting plates optionally a simple cylinder-typechopper or several flywheel choppers is/are positioned behind thelateral cutting device to shorten the stalks passing longitudinallythrough the straw-cutting machine.

The cylinder-type chopper corresponds in design and operation to theconventional construction with chopping bars passing laterally over thecylinder width. In a special design, the beater bars run in a screwshape laterally from one side to the other with the angle of claspingbeing greater than 360 degrees. In this way, the cutting barspractically always maintain engagement. The height of the cutting barscorresponds here roughly to the length to which the stalks are to beshortened. To support the discharge, a radial blower is assigned to thecylinder-type chopper as described above.

If flywheel choppers are positioned after the lateral cutting device, atleast two of these are provided so that the chopped stalks can bedistributed uniformly to both sides through the distribution hood. Theheight of the chopping bars corresponds here too roughly to the lengthto which the stalks are to be shortened. The drive of the flywheelchopper is performed in a manner not described in detail with beltdrives or bevel gears.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiment in accordance with the invention is disclosed in FIGS. 1to 10 with the accompanying descriptions:

FIG. 1 shows a longitudinal section through a straw-cutting machine witha stalk lateral cutting device and a following separation device bymeans of counter cutting plates for stalks passing through thestraw-cutting machine lengthways;

FIG. 2 illustrates a top view of the separation device of FIG. 1;

FIG. 3 illustrates how the cutting plates and the counter-bars areeccentrically relieved;

FIG. 4 illustrates a longitudinal section through the chopping cylinderwhich reveals the arrangement of the tang plates and the axial blowers;

FIG. 5 illustrates a cross-section through the chopping cylinderrevealing the positions of the tang plates to one another;

FIG. 6 illustrates a cross-section through an axial blower;

FIG. 7 illustrates a view of the knife-bearers;

FIG. 8 illustrates a view of the tang plates;

FIG. 9 illustrates a longitudinal section through a straw-cuttingmachine with a stalk lateral cutting device and a following separationdevice by means of cylinder-type choppers for stalks passing throughlengthways; and

FIG. 10 illustrates a longitudinal section through a straw-cuttingmachine with a stalk lateral cutting device and a following separationdevice by means of flywheel choppers for stalks passing throughlengthways.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a cross-section through a straw-cutting machine where thestalk lateral cutting device is associated with a stalk longitudinalcutting device positioned below it.

Here, the stalks (1) to be chopped fall from a straw outlet hood (2)onto the chopping drum (4) rotating in the direction of the arrow (3).Here, the stalks are picked up by tangs (6) with eccentrically relievedserrations on their front sides (5) and transported to the inlet area(7). The tang plates draw the stalks from here over cutting knives (8)fixed rigidly in pairs to the outside of a knife floor (9) on bearers(10) by means of screws (11) and limited downwardly by stops (12). Theknife plate or floor (9) runs roughly parallel to the chopping floor(13).

The knife floor (9) is pivoted in bearings (14) on the chopping floor(13). The cutting knives protrude with their front ends, which possesssharp cutting edges (15), through slits in the knife floor (9) and thechopping floor (13) between two tang plates (6) in each case with theirfront ends (17) up to the outer diameter of the cylinder roll (18).

The bearers (10) are supported on bolts (19) which are, in turn,supported in bearing plates (20). In this process, the bearers are drawndown to a stop (22) by a stroke (21) with that part of the cuttingknives protruding between the tang plates into the chopping area (23)being pressed upwards. If a hard foreign body not shown in any detailenters the inlet room (7) and is taken up by the tang plates there, thecutting knives yield backwards in the direction of the arrow (24).Independently of this, the knife floor (9) can yield with all cuttingknives in the direction of the arrow (25) around the swivel point (14).

Below the cutting knives, opposite cutting plates (26) are positioned onthe chopping floor (13) which opposite cutting plates (26) haveeccentrically relieved serrations on their front sides (27), theserrations agreeing in profile with the serrations on the front sides ofthe tang plate and both serrations agreeing up to a distance parallel onall sides of less than 3 mm. The opposite cutting plates are pivoted onbolts (28) and are pressed by means of a stroke (29) against anadjustable stop not described in any detail. The opposite cutting platesare divided into several segments of which each can yield singly andalone when a hard foreign body strikes. The counter bar (26) may bedivided over the width of the chopping cylinder (4) into segments, witheach single segment being able to be pivoted in a bearing. Thecounter-bar segments are drawn by strokes into the chopping areaindependently of one another and limited by the stop.

The stalks chopped in a lateral direction and a longitudinal directionis then discharged to the rear from the distribution hood (31) in thedirection of the arrow (30).

The lateral chopping device is designed in such a manner that the tangplates (6) are located on the mantel of the chopping cylinder (4) inseveral rows laterally over the width of the chopping cylinder (4), witha width of at least 25 mm, serrations on their front sides (5) and anintermediate space of at least 6 mm. Around the circumference of thetips (5) of the tang plates (6), the arc-shaped chopping floor (13) ispositioned on one side, with the chopping knifes (8) being fixed on anouter side thereof and reaching inwardly between the tang plates (6)through slits in the chopping floor (13) up to around 5 mm to the mantleof the chopping cylinder (4). The serrated (5) tang plates (6) arescrewed on in a removable manner. The chopping knives (8) are positionedto extend through an angle of more than 10° to the horizontal fromoutside to inside and downwardly.

FIG. 2 shows a view of the opposite cutting plates (26) in engagementwith the tang plates (6). Here, the segment-like division of theopposite cutting plates and the profile agreement of tang plate andopposite cutting plate can be seen. Here, the front sides (5), (27) ofthe opposite cutting plate and the tang plate engage in a serratedmanner parallel to each other at a distance a (32) of less than 3 mm.

FIG. 3 shows the undercut angles a (33) and β (34) of tang plates andopposite cutting plates. The undercut angles here are greater than 3degrees. Both angles can be of equal or different size as required.

FIG. 4 shows a longitudinal section through the chopping cylinder (4)revealing the arrangement of the tang plates (6). On both ends of thechopping cylinder (4) one axial blower each (35), (35') is positioned.Here, any number of ventilator blades (37) are positioned on plates(36), (36') connected to the front sides of the cylinder mantle. The air(39) sucked in through an aperture (38), (38') is blown into thedistribution hood (31) in the direction of the arrow (40), (40').

FIG. 5 shows the arrangement of the tang plate rows (6) in theirscrew-shaped passage over the cylinder mantle. Here, it is shown thateach first tang plate (6) marked by an "A" of a row on the circumferencehas the same angle position as the last tang plate marked by a "B" ofthe following or preceding row.

FIG. 6 shows a cross-section through an axial blower (35, 35'). Here,the air sucked in through an aperture (38) in the center of the blowerthrough the ventilator blades (36), (36') from out side the chopping boxis emitted through a discharge (41), (41') into the distribution box inthe direction of the arrow (40), (40').

FIG. 7 shows a view with an exemplary embodiment of the stalk lateralcutting device from the outside onto the knife floor (9) at a largerscale. Here are shown, for example, the bearers (10) on which thecutting knives (8) are rigidly fixed by screws (11). Here, the cuttingknives are limited downwardly by stops (12). The bearers (10) are, inturn, supported on bolts (19).

FIG. 8 shows a top view of any segment of the stalk lateral cuttingdevice with the interaction of tang plates (6) and cutting knives (8)being shown at an exploded scale. Here it can be seen how the choppingknives are positioned in the gap b (44) between tang plates lying nextto each other in each case.

FIG. 9 shows how a cylinder-type chopper (45) is positioned after thestalk lateral cutting device. Here, the stalk parts taken up by the tangplates and aligned lengthways are picked up by the chopping bars (46)and shortened in interaction with a counter-cutter (47). The choppingbars are here positioned on a cylinder mantle (42) laterally over thewidth of the straw-cutting machine in a spiral shape with one cylinderbar clasping spirally the cylinder mantle from one side to the other atan angle equal to or larger than 360 degrees. The chopped stalks arethen discharged through a distribution box (48) in the direction of thearrow (43).

FIG. 10 shows the assignment of flywheel choppers (49) behind thelateral cutting devices. Here, the stalks chopped in a lateral positionare passed on by the tang bars (6) in the direction of the arrow (50)through apertures (51) to the chopper housings (52) of several flywheelchoppers positioned next to each other together with the longitudinallyaligned, unchopped stalks. The chopping knives (54) fixed on a drivenchopping wheel (53) take up the longitudinally aligned stalk parts andshorten these in an interaction with a counter-cutter (55). The choppedstalks are then discharged in the direction of the arrow (56). Theflywheel choppers (49) can be swiveled out downwardly or upwardly eitherindividually or together.

I claim:
 1. A straw-cutting machine for the chopping of stalks behind agrain separation device of a combine harvester comprising thecombination of:a chopping cylinder with tangs of any shape on a cylindermantle, which cylinder is supported in a chopping housing with achopping floor on which fixed position opposite knives are located toform (i) a lateral chopping device by the interaction of the tangs withthe opposite knives, which lateral chopping device is positioned for theseparation of stalks lying laterally in the straw-cutting machine, withthe chopped stalks being discharged through a distribution hood, and(ii) a special chopper positioned in the distribution hood downstream ofthe lateral chopping device in the straw-cutting machine, for theseparation of stalks which pass through the lateral chopping device in alongitudinal direction.
 2. A straw-cutting machine according to claim 1,wherein the lateral chopping device is designed in such a way that thetang plates are located on the mantle of the chopping cylinder inseveral rows laterally over the width of the chopping cylinder with awidth of at least 25 mm, with serrations on their front sides and withan intermediate space distance of at least 6 mm and that around thecircumference of the tips of the tang plates, the chopping floor whichis arc-shaped is positioned on one side and on whose outside thechopping knives are fixed which reach inwardly between the tang platesthrough slits in the chopping floor up to around 5 mm to the mantle ofthe chopping cylinder.
 3. A straw-cutting machine according to claim 1,wherein the serrated tang plates are screwed on in a removable manner.4. A straw-cutting machine according to claim 1, wherein the choppingknives are fixed on a knife plate running roughly parallel to thechopping floor, with the knife plate being hung pivotably in bearings onthe chopping floor and having slits through which the chopping knivesprotrude through the chopping floor into the chopper.
 5. A straw-cuttingmachine according to claim 2, wherein the chopping knives are fixed onthe knife plate on knife bearers which are pivotable in the bearings. 6.A straw-cutting machine according to claim 3, wherein the choppingknives are fixed in pairs on a knife bearer (10).
 7. A straw-cuttingmachine according to claim 2, wherein the chopping knives are positionedrunning through an angle of more than 10 degrees to the horizontal fromthe outside to the inside and downwards.
 8. A straw-cutting machineaccording to claim 6, wherein the knife bearers are drawn against a stopagainst the knife floor by a stroke.
 9. A straw-cutting machineaccording to claim 3, wherein below the cutter knives on the choppingfloor (13) counter bars serrated on their front sides are positionedwhich reach in the chopping area with their serrations into theserrations of the tangs with both serrations agreeing in profile in sucha way that a parallel distance on all sides of less than 3 mm exists.10. A straw-cutting machine according to claim 7, wherein the counterbar is divided over the width of the chopping cylinder into segmentswith each single segment being able to be pivoted in a bearing.
 11. Astraw-cutting machine according to claim 10, wherein the counter-barsegments are drawn by strokes into the chopping area independently ofone another and limited by a stop.
 12. A straw-cutting machine accordingto claim 1, wherein on both ends of the chopping cylinder axial blowerslinked to it are positioned.
 13. A straw-cutting machine according toclaim 10, wherein the two axial blowers suck in air from outside andblow it into the distribution hood.
 14. A straw-cutting machineaccording to claim 1, said special chopper is constituted by, acylinder-type chopper located between the lateral cutting device and thedistribution hood with chopping bars positioned on said cylinder mantle.15. A straw-cutting machine according to claim 14, wherein the choppingbars are located on the cylinder mantle in a screw-shaped claspingmanner with the clasp being at least 360 degrees from the start of thechopping bar on one side up to the end on the opposite side.
 16. Astraw-cutting machine according to claim 1, wherein between the lateralcutting device and the distribution hood, at least two flywheel choppersare positioned which constitutes said special chopper.
 17. Astraw-cutting machine according to claim 16, wherein the flywheelchoppers can be swivelled out singly or severally downwards or upwards.18. A straw-cutting machine according to claim 14, wherein the chopperbars interact with a counter cutter mounted on the distribution hood.